package com.lqk.netty.http;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.*;
import io.netty.util.CharsetUtil;

import java.net.URI;

/**
 * 说明
 * 1. SimpleChannelInboundHandler 是 ChannelInboundHandlerAdapter 的子类
 * 2. HttpObject 表示客户端和服务器端相互通讯的数据被封装成 HttpObject
 */
public class HttpServerHandler extends SimpleChannelInboundHandler<HttpObject> {
    /*
        channelRead0 读取客户端数据
     */
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {

        // 判断 msg 是不是 HttpRequest 请求
        if (msg instanceof HttpRequest){

            System.out.println("msg 类型= " + msg.getClass());
            System.out.println("客户端地址：" + ctx.channel().remoteAddress());

            // 对特定资源进行过滤
            // 获取到
            HttpRequest httpRequest = (HttpRequest) msg;
            // 获取uri，过滤指定资源
            URI uri = new URI(httpRequest.uri());
            if ("/favicon.ico".equals(uri.getPath())){
                System.out.println("请求了 favicon.ico，不做响应");
                return;
            }

            // 回复信息给浏览器
            ByteBuf content= Unpooled.copiedBuffer("hello，我是服务器", CharsetUtil.UTF_8);
            // 构造一个 http 的响应，即 httpResponse
            FullHttpResponse httpResponse = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);

            httpResponse.headers().set(HttpHeaderNames.CONTENT_TYPE,"text/plain");
            httpResponse.headers().set(HttpHeaderNames.CONTENT_LENGTH,content.readableBytes());

            // 将构建好的 httpResponse 返回
            ctx.writeAndFlush(httpResponse);
        }

    }
}
